The present invention relates to a one-way clutch.
There is a one-way clutch mounted to an annular space formed between a driving side member and a driven side member for transmitting rotation of the driving side member in one direction to the driven side member via a sprag.
The one-way clutch is provided with a plurality of sprags arranged at an annular space between a driving side member and a driven side member in a circumferential direction thereof, two cages on an outer side and an inner side for retaining the sprags and an annular spring member for urging to erect the sprags at inside of the annular space by spring force thereof.
The outer side cage, the inner side cage and the spring member are respectively formed with pockets for sprags of numbers the same as a number of pieces of the sprags at a pitch of an equal angle in the circumferential direction and the sprags are contained in the pockets.
In the above-described constitution, when the driving side member is rotated relative to the driven side member in one direction, the respective sprags are erected at inside of the annular face between the two members along a radius direction thereof and stretched between the two members to be brought into a locked state and rotation of the driving side member in the one direction is transmitted to the driven side member. When the driving side member is rotated in a reverse direction relative to the driven side member, the respective sprags are brought into a fallen attitude to follow rotation of the driving side member and the driving side member ring is rotated idly relative to the driven side member.
Meanwhile, there is a case in which a value of necessary transmission torque of the above-described one-way clutch differs by a place of use even with the same dimension. What contributes to the transmission torque is the sprag and therefore, in the case of a one-way clutch having a large capacity of the transmission torque, a number of pieces of using the sprags is large and in the case of a one-way clutch having a small capacity of the transmission torque, the number of pieces of using the sprags is small.
In this way, according to the one-way clutch, the number of pieces of using the sprags frequently differs even with the same dimension.
In respective constituent parts of the one-way clutch, annular members of the outer side cage, the inner side cage and the like respectively include pockets for containing the sprags. In the annular member having a constant dimension, when the number of pieces of using the sprags is increased or reduced, it is necessary to increase or reduce the number of pockets by changing a pitch between the pockets. In order to fabricate the annular member of the outer side cage or the like having a different number of the pockets, a die in correspondence therewith needs to newly prepare and a problem that cost is increased is posed.